The CONSOLE tandem is a tool for optimization-based design of a large class of systems. The essential requirements are that a simulator be available for evaluating the performance of instances of the system under consideration and that the parameters to be optimally adjusted vary over a continuous (as opposed to discrete) set of values. Todate, CONSOLE has been used on problems as diverse as design of a controller for a flexible arm, an aircraft, or a copolymerization reactor. The manual is organized as follows. In Chapter 1, the ideas and principles upon which CONSOLE is constructed are outlined and the design methodology underlying CONSOLE is sketched. Chapter 2 introduces the novice user to CONSOLE by way of a simple tutorial example. This chapter is strongly recommended to new users as it leads them step by step through a CONSOLE session. Chapter 3 is entirely devoted to CONVERT. It includes a thorough description of the different data types, assignments and commands that form the CONVERT syntax. Chapter 4 discusses SOLVE. The essential features of the optimization algorithm are outlined and the operation of SOLVE SOLVE is discussed. Special attention is given to the interactive capabilities of SOLVE, in particuar the Pcomb display. In Chapter 5, the question of using an interface between SOLVE and simulators of the user's choice is discussed. A general structure is given. Finally, Chapter 6 presents two design examples. Appendices A and B consist in reference manuals, for CONVERT and SOLVE respectively.